Tower extractor for municipal wastes

ABSTRACT

A tower extractor and method to continuously and coarsely or roughly separate paper, film plastic products and like, lighter materials from the heavier materials in a relatively large volume conglomerate of mixed solid municipal wastes or refuse. The separation occurs as the result of an airstream being directed into the conglomerate of mixed solid wastes as the mixed solid wastes begin to slide down a chute at least 30 feet long disposed at an angle of about 60* to 80* from vertical in a separation chamber. The volume and pressure of the airstream are selected so as to cause an initial separation and suspension of at least a portion of the lighter materials from the heavier materials as the waste descends down the chute. While a portion of the lighter materials is air suspended, the heavy materials and the remaining portions of the waste mixture flow down the chute and the mixture is further separated into a light fraction and a heavy fraction. The separation occurs because the components in the light fraction move at a slower rate than the components in the heavy fraction. As a result, the light components stratify above the heavy component and are drawn out of the separation chamber as a light fraction, preferably by suction. The heavier materials remain in contact with the chute and are separately discharged out of the separation chamber.

United States Patent [1 1 Brown 1 Sept. 17, 1974 TOWER EXTRACTOR FORMUNICIPAL WASTES [76] Inventor: Victor Brown, 2208 Shadowdale,

Related US. Application Data [63] Continuation-impart of Ser. No.125,516, March 18,

1971, abandoned.

[58] Field of Search 209/133 T, 139 R, 134-138, 209/147, 154, 20, 3, 4,477, 483, 19, 471, 479; 131/146; 241/68, 79.1, 19, 24

[56] References Cited UNITED STATES PATENTS 888,156 /1908 Gillette209/139 R 1,517,595 12/1924 Stebbins 209/135 1,579,660 4/1926 Reilly209/ 1,888,372 11/1932 Bramwell 209/139 R 2,018,010 10/1935 Chance209/471 2,186,167 1/1940 Eismann 209/37 2,203,821 6/1940 I-Iinchman209/139 R X 2,210,103 8/1940 Stoner 209/135 X 2,978,103 4/1961 Cowher209/135 3,010,576 11/1961 Harte et a1 209/ 3,358,830 12/1967 Duncan209/136 X 3,524,594 8/1970 Anderson et a1. 241/19 3,650,396 3/1972Gillespie et al.... 209/3 3,738,483 6/1973 MacKenZie 209/137 X FOREIGNPATENTS OR APPLICATIONS 1,302,591 7/1962 France 209/479 OTHERPUBLICATIONS Suthau, Auslegeschrift 1,091,952 ll/ 1960.

Primary ExaminerFrank W. Lutter Assistant ExaminerRa1ph J Hill Attorney,Agent, or FirmMolinare, Allegretti, Newitt & Witcoff [5 7] ABSTRACT Atower extractor and method to continuously and coarsely or roughlyseparate paper, film plastic products and like, lighter materials fromthe heavier materials in a relatively large volume conglomerate of mixedsolid municipal wastes or refuse. The separation occurs as the result ofan airstream being directed into the conglomerate of mixed solid wastesas the mixed solid wastes begin to slide down a chute at least 30 feetlong disposed at an angle of about to from vertical in a separationchamber. The volume and pressure of the airstream are selected so as tocause an initial separation and suspension of at least a portion of thelighter materials from the heavier materials as the waste descends downthe chute. While a portion of the lighter materials is air suspended,the heavy materials and the remaining portions of the waste mixture flowdown the chute and the mixture is further separated into a lightfraction and a heavy fraction. The separation occurs because thecomponents in the light fraction move at a slower rate than thecomponents in the heavy fraction. As a result, the light componentsstratify above the heavy component and are drawn out of the separationchamber as a light fraction, preferably by suction. The heaviermaterials remain in contact with the chute and are separately dischargedout of the separation chamber.

17 Claims, 3 Drawing Figures TOWER EXTRACTOR FOR MUNICIPAL WASTES CROSSREFERENCE TO RELATED APPLICATION This application is acontinuation-in-part of my copending application Ser. No. 125,516 filedMar. 18, l97l now abandoned.

BACKGROUND OF THE INVENTION This invention relates to a novel andimproved tower extractor, and more particularly, to a novel and improvedtower extractor for continuously, coarsely or roughly separating paper,film plastic products and like, lighter materials from the heaviermaterials in a relatively large volume of conglomerate of mixed solidmunicipal wastes or refuse.

The improved tower extractor of the present invention is utilized as apart of a new, overall system for the treatment of mixed solid wastes orrefuse, such as the mixed solid wastes which originate from municipal,commercial and industrial sources. This new system is designed to be analternative to 'the common practice of simply disposing of refuse orsolid wastes in land fills or in refuse dumps.

In this new system, the refuse is separated into its component parts sothat each part may be separately processed, and to a large extent, bereclaimed or converted into usable materials or energy. In a time whenthe public is becoming increasingly aware of problems relating toecology and energy conservation, such new systems of effectivelyhandling municipal wastes are of significant importance.

For example, the paper and fiber portion of municipal waste canrepresent up to 60 percent of the total waste. This material, whenseparated from the total waste, has a BTU value of at least 6,000BTU/lb. Typically the paper and fiber portion has a BTU value of about8,000 BTU/lb. Because of this high heat value, the paper, etc., could bea valuable fuel source.

In order for a system for the separation of municipal waste to becommercially attractive, it is of critical importance that the componentparts of the refuse or solid wastes be inexpensively and quicklyseparated. The tower extractor of the present invention satisfies theserequirements in a novel and unique manner and provides an economical andfacile means for coarsely or roughly separating paper, film plasticproducts and like, lighter materials from the heavier materials in amixed conglomerate of refuse or municipal solid wastes at or near thebeginning of the separation process in the system. My improved towerextractor is relatively inexpensive to manufacture and maintain and iscapable of handling a high volume of solid wastes or refuse whileobtaining a relatively good quality, rough separation at minimal cost.

SUMMARY OF THE INVENTION More specifically, my novel and improved towerextractor includes a separation chamber having a relatively steep chutedisposed therein. This chute must be inclined at an angle of about 60 toabout 80 and be of sufficient length to permit the light and heavycomponents in municipal waste to reach their terminal velocity as theydescend down the chute. For a small capacity system, this length must benot less than 30 feet. The length should be proportionately longer forlonger capacity systems. A first conveyer is utilized to elevate theconglomerate of solid wastes or refuse to be separated to the upper endof the chute in the separation chamber. Preferably, the conglomerate ofmixed solid wastes is shredded prior to its introduction into theseparation chamber to facilitate the separation of the waste componentsin the chamber. As the solid wastes are dropped off at the discharge endof the first conveyer and onto the upper end of the chute, a relativelyhigh volume, high pressure stream of air is directed into the wastes.This airstream causes at least a portion, if not all of the materials inthe wastes to become momentarily suspended or airborne. However, theheavier materials in admixture with some light material soon fall backonto the chute and continue to slide down to the lower end of the chute.As this mixture slides down the chute, the mixture separates into aheavy fraction in direct contact with the chute and a light fractionstratified above the heavy fraction with the heavy fraction moving at afaster velocity than the light fraction. This stratification is due tothe fact that the components in the heavier fraction have a smallersurface area and are more dense than the paper, etc., components in thelight fraction. As a consequence, the components in the heavy fractionmove at a higher velocity than the less dense, higher surface arealighter components. As the mixture flows, the lighter materials migratetoward the top of the heavy layer and stratification occurs. Thisstratification would occur if the mixture merely flowed down the steeplyinclined chute without the need for the airstream. However for efficientseparations to occur, a prohibitively long chute is necessary. Theutilization of the airstream substantially lowers the length of thechute required. A second conveyer is positioned adjacent to the lowerend of the chute and is utilized to transport the heavier materialsout'of the separation chamber.

The lighter materials, such as paper, film plastic products and thelike, initially are in suspension or remain airborne in the separationchamber due to the volume and pressure of the airstream and due to thedomed shape of the upper portion of the separation chamber. This allowsthe heavier materials to make first contact with the chute. The lightermaterials are ultimately drawn out of the separation chamber, whilestratified above the heavier materials by suction. Thus, through theutilization of the novel and improved tower extractor of my invention,an extremely satisfactory, rough separation of conglomerate municipalsolid wastes or refuse can be achieved.

Accordingly, it is a primary object of my present invention to provide anovel tower extractor for coarsely and roughly separating paper, filmplastic products and like, light materials from heavier materials in aconglomerate of mixed municipal solid wastes or refuse.

Another object of the present invention is to provide a novel towerextractor wherein the materials to be separated are conveyed to theupper end of a-steeply inclined chute in a separation chamber; whereinas the materials begin to fall down the chute, a relatively high volume,high pressure stream of air is directed into the materials. Preferably,the stream causes at least a portion of the materials, particularly thelight materials, to at least temporarily become suspended or airborne;wherein the heavier materials thereafter drop or fall back onto thechute and slide down the chute; and wherein due to the slope and lengthof the chute, the

materials stratify into a light fraction and a heavy fraction.

Still another object of the present invention is to provide a noveltower extractor wherein a first conveyor is utilized to convey thematerials to be separated to the upper end of the chute in theseparation chamber; wherein a second conveyor is utilized to convey theseparated, heavier materials from the separation chamber; and whereinthe stratified lighter materials are withdrawn from the separationchamber by suction.

A related object of the present invention is to provide a novel andimproved tower extractor of the type described wherein the angle of theairstream may be adjusted with respect to the material to be separated.

These and other objects and advantages of my invention will be apparentfrom the following description of the preferred embodiment of myinvention.

DESCRIPTION OF THE DRAWINGS Referring to the drawings wherein likereference numerals indicate like parts throughout the figures:

FIG. 1 is a partial vertical cross-sectional view of a shredder, supplyconveyor, and tower extractor embodying the principles of my invention.

FIG. 2 is a cross-sectional view taken along section line 2-2 in FIG. 1,and

FIG. 3 is a detailed plan view of the riffles positioned within thetower extractor.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the towerextractor of my invention is shown generally at 11 and is utilized tocoarsely separate the lighter materials and the heavier materials inmixed solid wastes or refuse such as the type which originate frommunicipal, commercial and industrial sources. The extractor 11 isparticularly suitable for use in the initial portion of the new overallsystems for treatment of mixed solid waste or refuse materials which arebeing developed as an alternative to the common practice of simplydisposing of refuse or solid wastes in land fills or in refuse dumps.

Prior to passage to the extractor 11, the raw solid wastes 2 (FIG. 2)collected from the general public is first crushed and shredded inshredder 1. It has been discovered that shredding enhances theefficiency of the extractors. Preferably, the raw solid wastes 2 areshredded so that the paper portion of the waste is between l and 12inches in cross section. Shredder 1 comprises a rotor 3 havingpositioned on the arms of the rotor grinding members 4. Grinding members4 shred the waste by a shearing action between the members 4 and theinterior of shredder 1. The waste is further shredded by the forcing ofthe waste by members 4 through the narrow gaps in grate 5. The rawshredded waste 6 is then discharged onto the conveyor 26 and passed toextractor 11 for separation.

The extractor 11 includes an air separation chamber 12 which isgenerally disposed so that its longitudinal axis is disposed at an anglewith respect to the vertical. The chamber 12 has inlet opening 13adjacent to its upper end 14, and has a light material discharge opening15 and a heavy material opening 16 adjacent to its lower end 17.

As shown in FIG. I, the discharge openings 15 and 16 are spaced fromeach other, with the opening 15 being spaced above the opening 16 andbeing separated from the opening 17 by an inwardly curved, generallytriangular wall section 18. The light material discharge opening 15 isgenerally tubular in form, with the initial part of the tubular openingbeing defined by the wall section 18 which also defines the initialportion of the heavy material discharge opening 16.

The lowermost or bottom wall 19 of the chamber 12 defines and functionsas a chute 21. The upper end 22 of the chute 21 is positioned adjacentto the inlet opening 13 and the lower end 23 of the chute is positionedadjacent to and forms a part of the heavy materials discharge opening16. The uppermost or top wall 24 of the chamber 12 is generally parallelto the wall 19 except adjacent to the upper end 14 of the chamberwherein a dome-like section 25 is formed for the reasons hereinafterexplained.

It is necessary that the chute be inclined at an angle of 80 and be ofsufficient length to allow the light and heavy components in its wasteto reach their terminal velocity so that stratification of thecomponents occurs. This stratification is further enhanced by addingriffles 9 to the surface of chute 21 which extends laterally across theentire width of the chute. As illustrated in greater detail in FIG. 3,riffles 9 are generally triangular in shape with the base of thetriangle facing downstream. The base of the triangle generally is aboutI l.5 inches high and the hypotenuse is positioned at an angle of about30 45 to the surface of chute 21. Riffles 9 are spaced about 8 12 feetapart along the length of chute 21. Typically three to six riffles areused in a given extractor, the exact number being a function of the sizeand capacity of the unit.

A conventional, endless, conveyor 26 is positioned adjacent to the upperend 14 of the chamber 12. The conveyor 26 extends into the chamber 12through the inlet opening 13 so that its head pulley 27 is positionedwithin the interior of the chamber 12 and so that the path along whichmaterials are conveyed thereon is generally perpendicular to the planeof the chute 21. The conveyor 26 is disposed at an angle with respect tothe vertical (and with respect to the longitudinal axis of chamber 12)so that it elevates and conveys the conglomerate of mixed solid wastesor refuse materials to be separated into the interior of the separationchamber 12.Preferably, the mixed solid waste and refuse materials areshredded prior to their being conveyed by the conveyor 26 since suchshredding tends to improve the degree of separation obtained in thetower extractor 11. When the materials being conveyed reach the upperend of the conveyor 26, i.e., the head pulley 27, the conveyor 26 isarranged so that the waste and refuse materials are dropped onto theupper end 22 of the chute 21.

An air stream inlet 28 is defined by a portion 29 of a duct 31 and islocated adjacent to but immediately below the head pulley 27 andimmediately above the upper end 22 of the bottom wall 19. The duct 31 isconnected to the outlet of a conventional, adjustable air blower 32 sothat a continuous, high volume, high pressure stream of air may beintroduced into the interior of the separation chamber 12 through theinlet 28. The stream of air introduced through the inlet 28 may bevaried as to velocity and pressure, by adjusting the operation of theblower 32, so as to provide the optimum separation, considering thelocal conditions of the mixture, i.e., the amount of moisture,composition, etc.

As shown in FIG. 2, the portion 29 of the duct 31 is rectangular incross-section and is arranged so that it extends completely across thefull width of the conveyor 26 and so that the steady forceful air blastflowing through the inlet 28 bears on the mixed refuse or solid wastefalling off the head pulley. The rectangular configuration of theportion 29 of the duct 31, which defines the inlet 28, is utilized toinsure that the airstream bears on all the falling particles of refuseor solid waste. The portion 33 of the duct 31, upstream from the inlet28, may have a more conventional crosssection, such as a round or squareconfiguration. The portions 29 and 33 of the duct 31 are interconnectedby a transition portion 34.

An adjustable baffle plate 35 is located within the portion 29 of theduct 31, just upstream from the inlet 28, and this plate 35 extendsacross the portion 29. The plate 35 is secured to a rod 36 whose endsare journaled in the sides of the portion 32, adjacent the sides of theconveyor 26. A handle 37 is connected to an extended end of the rod 36and is utilized to adjustably rotate the rod 36 about its longitudinalcentral axis. Rotation of the rod 36 results in pivotal movement of theplate 35 within the portion 29 of the duct 31. Locking means, not shown,may be used to hold the plate 35 is any pre-selected position within theduct 31. The purpose of permitting adjustment of the angular dispositionof the plate 35 is to enable the user of the tower extractor to adjustthe direction of airstream introduced into the interior of the chamber12 through the inlet 28, so as to obtain optimum separation for thesolid wastes or refuse being processed.

A second conventional endless conveyor 38 is positioned adjacent to theheavy material discharge opening 16. The conveyer 38 is generallyhorizontally disposed and' is adapted to receive the separated heavymaterials 7 from the lower end 23 of the chute 21. The conveyer 38 isutilized to convey these heavy materials 7 to the next step in theoverall process.

The light material discharge opening is connected to a source ofsuction, shown generally at 39, which causes the light materials 8stratified over heavy materials 7 in the interior of the chamber 21 nearthe end of lower end 23 of chute 21 to be withdrawn from the chamber 12.Upon the light materials 8 being withdrawn from the chamber 12, they tooare conveyed by conventional means, not shown, to the next processingstep in the overall treatment process.

OPERATION The operation of the improved tower extractor is as follows: Arelatively large volume of mixed solid waste or refuse materials 2 to beroughly or coarsely separated is continuously conveyed into the inlet ofcrusher 1 wherein the waste is ground into a waste stream 6 of smallsize. The ground waste is then continuously conveyed into the upper end14 of the chamber 12 by the conveyer 26. The shredding or crushing ofmaterials 2 improves even more the efficiency of the separationoperation. The waste or refuse materials are conveyed by the conveyer 26along a first path, disposed at an angle with respect to the vertical,into the interior of chamber 12 through the opening 13. As the waste orrefuse materials reach the upper end or the head pulley 27 of theconveyer 26, they fall, by gravity, off the conveyer and onto the upperend 22 of the chute 21. At this point, i.e., as the waste or refusematerials fall away from the conveyer 26, a high volume, high pressurestream of air from blower 32. is directed into the falling materials. Asnoted previously, the direction and intensity of the airstream isregulated by the position of the adjustable plate 35.

The airstream causes at least a portion of the materials to bemomentarily suspended in the air or to become temporarily airborne.However, the heavier materials in the conglomerate of mixed materialsand at least a portion of the light materials in admixture with theheavy materials tend to fall, by gravity, back onto the chute 22 andagain, by gravity, slide down the chute 22 to its lower end 23.

In contrast to the heavy materials, at least a portion of the lightermaterials, such ss paper, film plastic products, and the like, are atleast momentarily held in air suspension by the airstream in the upperdome-like section 25 and along the upper wall 24 of the chamber 12. Theamount of materials in air suspension results from selection of thevolume, velocity and pressure of the airstream introduced into theinterior of the chamber 12.

Those materials not in air suspension slide down chute 22. As theydescend down the chute, the components reach their terminal velocitywith the light materials 8 stratifying over heavy materials 7 wherebythis stratification allows the materials to be separated at the end ofthe chute by the cooperation of curved wall 18 which is adapted toextend to the interface between the two separately moving strata and thesuction, induced in the inlet 15 by the suction means 39. This causesthese stratified lighter materials to be drawn from the section 25 alongthe upper wall 24 and into and out of the discharge opening 15.

As mentioned earlier, the stratification between light materials andheavy materials occurs because of the difference in density and theratio of density to surface area in the waste mixture. As the mixturedescends down chute 21 the lighter materials, because of their greaterresistance to air tend to flow at a lower terminal velocity than theheavy materials. As a consequence, the flowing light materials rise tothe top of the flowing heavy materials and form a slower moving lightstrata which can be readily removed from the separation chamber.

From the foregoing it will be apparent that my novel and improved towerextractor provides an expeditious and facile means for roughly orcoarsely separating the lighter materials from the heavier materialsfrom a conglomerate of mixed municipal solid wastes or refuse, andincreases the efficiency and effects of the overall waste or refusetreatment process. Moreover, the novel and improved tower extractor ofthe present invention does not utilize many movable parts and the partsutilized, for the most, are standard, readily available parts, so thatthe tower extractor may be operated with a minimum of maintenance andoperational expenses.

While in the foregoing, there has been provided a detailed descriptionof the preferred embodiment of the present invention, it is to beunderstood that all modifications obvious to those having ordinary skillin the art are to be included within the scope of the invention asclaimed.

1 claim:

1. A tower extractor for continuously, coarsely separating paper, filmplastic products and like, lighter materials from the heavier materialsin a conglomerate of mixed municipal solid wastes, comprising:

i. a separation chamber having an upper portion and an inlet opening, alight material discharge opening and a heavy material discharge openingspaced below said upper portion, with the inlet opening, the'lightmaterial discharge opening, and the heavy material discharge openingbeing spaced from each other with the heavy material opening and lightmaterial discharge opening spaced below the inlet opening;

ii. means for moving the conglomerate of mixed municipal solid wastes tobe coarsely separated into the air separation chamber means, through theinlet opening thereof, along a first path;

iii. means for providing an airstream;

iv. means for passing said airstream into the separation chamber meansso that the air stream axis intersects said first path adjacent to theinlet opening of the air separation chamber means, said airstream beingof sufficient pressure and volume so that at least a portion of thepaper, film plastic products-and like, lighter materials become at leastmomentarily airborne, and are partially separated from the heaviermaterials in the conglomerate of mixed municipal solid wastes;

v. a chute portion positioned within said separation chamber at least 30feet long and which slopes relatively steeply downward at an angle ofabout 60 to about 80 and has its upper end adjacent to the inlet openingin the separation chamber, the chute portion being positioned below thefirst path and said axis of said airstream to initially receive theheavier materials that fall away from said first path and slide downsaid chute portion after passing the point of the intersection betweensaid airstream and said first path, said chute further separating thecomponents in said waste as they slide down the chute;

vi. means for removing the heavier materials in the conglomerate ofmixed municipal solid wastes from the separation chamber means throughthe heavy material discharge opening; and vii. means for removing thelight paper, plastic film products and like, lighter materials from theseparation chamber means through the light material discharge opening.2. The tower extractor described in claim 1, wherein said first path isdisposed at a first angle with respect to I the vertical and saidairstream is directed from below products and like, lighter materialsfrom the air separation chamber means.

4. The tower extractor described in claim 1, wherein the means formoving the conglomerate of mixed municipal solid wastes into theseparation chamber is a first conveyer which has its discharge endlocated within the air separation chamber means adjacent to the inletopening thereof; and wherein said airstream intersects said first pathadjacent to the discharge end of the first conveyer.

inclined with respect to the vertical and with respect to thelongitudinal axis of the first conveyer and so that said airstreamintersects said first path at, point downstream, but adjacent to, thedischarge end of the conveyer.

6. The tower extractor described in claim 5 wherein the means forremoving the heavier materials includes a second conveyerpositioned-adjacent to the lower end of the chute portion and extendingout of the separation chamber through the heavy material dischargeopening in the separation chamber.

7. The tower extractor described in claim 6 wherein the means forremoving the suspended paper, plastic film products and like, lightermaterials includes suction means which is connected with the lightmaterials discharge opening in the separation chamber and which removesthe paper, plastic film products and like, lighter materials from theseparation chamber.

8. The tower extractor described in claim 7 wherein the means fordirecting said airstream is adjustable to permit said axis of saidairstream to intersect said first path at various angles.

9. The tower extractor of claim 1 which includes means for shredding thesolid wastes prior to its introduction into the separation chamber.

10. The tower extractor of claim 1 which includes an inwardly extendingwall positioned between the light material discharge opening and theheavy material discharge opening to intercept the light'fraction in saidchamber. I

11. The tower extractor of claim 1 which includes riffles on the surfaceof said chute.

12. A method for continuously coarsely separating paper film plasticproducts and like lighter materials from the heavier components in aconglomerate of mixed municipal solid wastes which comprises the stepsof:

i. passing a mixed municipal solid waste down a chute inclined at anangle of about 60 to about and of sufficient length to permit thecomponents in the waste to reach their terminal velocity and to stratifysaid wastes into a slower moving upper light fraction and a fastermoving heavy fraction;

ii. contacting said waste stream with a high velocity air stream as thewaste is about to descend down said chute to enhance saidStratification; and

iii. separating said light fraction from said heavy fraction.

13. A method as in claim 12 wherein said light fraction is separated bydrawing said fraction into a suction.

14. A method as in claim 12 which includes grinding said waste prior topassage down said chute.

15. A method as in claim 14 wherein the waste is ground to provide alight fraction wherein the light waste is one to twelve inches incross-section.

16. A method as in claim 12 wherein said air stream suspends at least aportion of said waste in air before passage down said chute.

17. A method as in claim 12 wherein said chute is at least 30 feet long.

2. The tower extractor described in claim 1, wherein said first path isdisposed at a first angle with respect to the vertical and saidairstream is directed from below said first path whereby all materialsbecome momentarily air suspended.
 3. The tower extractor described inclaim 1, wherein the means for removing the suspended paper, plasticfilm products and like, lighter materials includes suction meansconnected with the light materials discharge opening and which removesthe paper, plastic film products and like, lighter materials from theair separation chamber means.
 4. The tower extractor described in claim1, wherein the means for moving the conglomerate of mixed municipalsolid wastes into the separation chamber is a first conveyer which hasits discharge end located within the air separation chamber meansadjacent to the inlet opening thereof; and wherein said airstreamintersects said first path adjacent to the discharge end of the firstconveyer.
 5. The tower extractor described in claim 1 wherein thelongitudinal axis of the first conveyer is inclined with respect to thevertical; wherein the means for providing said airstream is positionedbelow the discharge end of the first conveyor; wherein the means fordirecting said airstream is arranged so that said airstream is inclinedwith respect to the vertical and with respect to the longitudinal axisof the first conveyer and so that said airstream intersects said firstpath at point downstream, but adjacent to, the discharge end of theconveyer.
 6. The tower extractor described in claim 5 wherein the meansfor removing the heavier materials includes a second conveyer positionedadjacent to the lower end of the chute portion and extending out of theseparation chamber through the heavy material discharge opening in theseparation chamber.
 7. The tower extractor described in claim 6 whereinthe means for removing the suspended paper, plastic film products andlike, lighter materials includes suction means which is connected withthe light materials discharge opening in the separation chamber andwhich removes the paper, plastic film products and like, lightermaterials from the separation chamber.
 8. The tower extractor describedin claim 7 wherein the means for directing said airstream is adjustableto permit said axis of said airstream to intersect said first path atvarious angles.
 9. The tower extractor of claim 1 which includes meansfor shredding the solid wastes prior to its introduction into theseparation chamber.
 10. The tower extractor of claim 1 which includes aninwardly extending wall positioned between the light material dischargeopening and the heavy material discharge opening to intercept the lightfraction in said chamber.
 11. The tower extractor of claim 1 whichincludes riffles on the surface of said chute.
 12. A method forcontinuously coarsely separating paper filM plastic products and likelighter materials from the heavier components in a conglomerate of mixedmunicipal solid wastes which comprises the steps of: i. passing a mixedmunicipal solid waste down a chute inclined at an angle of about 60* toabout 80* and of sufficient length to permit the components in the wasteto reach their terminal velocity and to stratify said wastes into aslower moving upper light fraction and a faster moving heavy fraction;ii. contacting said waste stream with a high velocity air stream as thewaste is about to descend down said chute to enhance saidstratification; and iii. separating said light fraction from said heavyfraction.
 13. A method as in claim 12 wherein said light fraction isseparated by drawing said fraction into a suction.
 14. A method as inclaim 12 which includes grinding said waste prior to passage down saidchute.
 15. A method as in claim 14 wherein the waste is ground toprovide a light fraction wherein the light waste is one to twelve inchesin cross-section.
 16. A method as in claim 12 wherein said air streamsuspends at least a portion of said waste in air before passage downsaid chute.
 17. A method as in claim 12 wherein said chute is at least30 feet long.